1. Field of the Invention
The present invention relates to a method for producing liquid discharge heads that discharge liquid and, more specifically, it relates to a method for producing ink jet recording heads that discharge recording liquid droplets used in an ink jet recording method.
2. Description of the Related Art
Examples of liquid discharge heads for discharging liquid include ink jet recording heads used in an ink jet recording method, which discharge ink onto recording media to perform recording.
An ink jet recording head (recording head) includes a substrate that has, at least, a plurality of discharge ports through which ink is discharged, an ink flow path communicating with the respective discharge ports, a supply port for supplying the flow paths with ink, and discharge-energy-generating elements for applying discharge energy to the ink in the flow paths. Typically, a silicon (Si) substrate is used as a substrate, and an ink supply port communicating with an ink flow path is formed so as to penetrate the substrate.
Japanese Patent Laid-Open No. 2005-169993 discloses a method for producing an ink jet recording head that has a beam formed at an ink supply port to increase the mechanical strength of a silicon substrate. In this method, a first mask 7 having two openings is formed on a rear surface of the silicon substrate, and dry etching is performed through the two openings obliquely with respect to the rear surface of the silicon substrate to form two grooves. Thereafter, crystal anisotropic etching is performed through the grooves toward the substrate surface to form an ink supply port 10, and a portion left unetched between the grooves in the rear surface of the substrate constitutes the beam.
However, in the above-described method, anisotropic etching has to be performed after oblique etching is performed twice. That is, oblique etching (dry etching), mask formation, and anisotropic etching for allowing the grooves to penetrate to the ink supply port surface have to be performed. Therefore, the number of steps is large, which imposes a heavy burden on the manufacture thereof.